Air bubbles or blisters in new pebble finished pool

[rporonga]

We just had our new pool finished with pebble finish. While doing the troweling, air bubbles kept appearing. They troweled several times, but in the end there are lots of small bumps, which I believe are air bubbles.
The pool builder is ignoring the issue. I am concerned that over time this will lead to delamination.
Is this an issue? If so, what should I do? I doubt the pool builder will be willing to refinish the pool.

 

[kimkats]

What happens if you put a needle or such in one of the bubbles?

 

[Bperry]

We just had our new pool finished with pebble finish. While doing the troweling, air bubbles kept appearing. They troweled several times, but in the end there are lots of small bumps, which I believe are air bubbles.
The pool builder is ignoring the issue. I am concerned that over time this will lead to delamination.
Is this an issue? If so, what should I do? I doubt the pool builder will be willing to refinish the pool.

Are they air bubbles or water weeping from under the surface? Definitely doesn’t look normal.

 

[ajw22]

Welcome to TFP.

Let's ask @onBalance @AQUA~HOLICS

 

[AQUA~HOLICS]

Did you tap on any of them to see if they sound hallow?
I have seen them before but not in such numbers.

 

[rporonga]

I have not tried tapping on them. The finish was new, and they told me not to walk inside the pool. Now it is full of water, and I will have to wait for the startup procedure before I can go in it. I saw those bubbles while they were troweling the plaster, and they kept coming back again. I asked them at the time, and they said it was normal and that they would go away as the pebble finish dried, but they did not go away. Their plaster supervisor claims they are solid, by just looking at the picture, which I don't trust.

 

[Dirk]

The pool builder is ignoring the issue.

He may not be able to. Was the finish a name brand, like PebbleTec®, or was it the builder's own do-it-himself pebble finish?

If the former, then there would be (should be) a PebbleTec warranty, which should cover installation issues like this. If the builder will not address the issue, then PebbleTec can be brought in to do so.

PS. Welcome to TFP, by the way. Sorry it is under these circumstances, but we're still glad you found us! We'll do what we can to help you figure this out.

 

[MAPR-Austin]

What was the prop method prior to pebble install?

Air bubbles like those pop up on the floor a lot when still on spikes, but its rare to see so many on the walls like that. Some air pockets go away when you trowel them, sometimes they have to be poked/cut to release the air.

Once the surface is hard, there isn't anything I know of that can remove them.

At least they didn't tell you that once the pool is full, the water pressure will push those bubbles flat...

 

[onBalance]

Now that the pool is full of water, please take a photo of a wall looking down from the deck above and post it here.

 

[rporonga]

>> Was the finish a name brand, like PebbleTec®, or was it the builder's own do-it-himself pebble finish?
It is called Pebble Plus: Maui Blue | Pebble Plus
I just called their number, and it turns out it is the pool builder. It is a large company, so they must have their own branded finish.

>> What was the prop method prior to pebble install?
They power washed the shotcrete (which had been shot several months ago, delay due to needing to finish the pavers around pool) and then shot the surface, 2 passes on the walls and 1 pass on the floor.
It was a large team, one person troweling each area. The shotcrete had large cracks all around since it was shot, and lumps here and there that survived the power washing. They also dug a large hole in the floor for the pump, which they did not use in the end because it was not the lowest point. The large hole exposed a piece of rebar. When I noted the rebar, they "painted" the rebar with grey PVC conduit glue, and filled it with plaster during plastering.

>> At least they didn't tell you that once the pool is full, the water pressure will push those bubbles flat...
They told me they are solid, no air inside, but did not do anything other than looking at the above picture to state that. They said it is a hand made product, and unevenness is to be expected. They don't acknowledge it is air bubbles. They refer me to their 10 year warranty in case I have any issue.

>> Now that the pool is full of water, please take a photo of a wall looking down from the deck above and post it here.
Will do later this evening. May not be visible though. I think the picture I posted showed the issue due to the angle of the lighting.

 

[Dirk]

I just called their number, and it turns out it is the pool builder. It is a large company, so they must have their own branded finish.

OK, so no help from a major finish provider. Bummer. He'll either honor his own warranty or he won't.

The shotcrete had large cracks all around since it was shot

Hmm, that doesn't sound good. Our other experts will have to weigh in about that. But if the cracks are sever enough, that they penetrate the shell, that could expose the rebar from the outside. Did you get any pictures of these cracks?

The large hole exposed a piece of rebar. When I noted the rebar, they "painted" the rebar with grey PVC conduit glue, and filled it with plaster during plastering.

That too will need to be analyzed by our experts, if that "fix" was sufficient. @JamesW, thoughts about the shell and this once-exposed rebar?

They said it is a hand made product, and unevenness is to be expected. They don't acknowledge it is air bubbles.

Yes, that is the standard line when pool owners see their finish at night with the pool light on for the first time and see all sorts of lumps and bumps. That excuse is legit, the unevenness is expected. But that does not cover what you've got. Those air bubble bumps are not normal nor expected, not in that number anyway (IMO).

They refer me to their 10 year warranty in case I have any issue.

Is that warranty in writing? Or just something the builder refers to? If in writing, what does it say about defects in material and workmanship? Keep in mind a warranty, no matter the duration, is only as good as its provider, and only lasts as long as the provider is in business. Did your builder offer a warranty for the shell? That is often a "lifetime" warranty, but again, that's not your lifetime, nor the lifetime of your pool, it's the lifetime of his business.

At some point, you will need to decide if you can live with the finish as is, or if you want to pursue a fix. And then you'll need to decide what you have the stomach for in that pursuit.

 

[Dirk]

A. This type of lump, visible when light shines across it, is what they generally refer to as "expected." The surface is hand troweled, and this is the result. It's acceptable. The surface is not going to be ultra flat.

B. This is a more extreme version of an expected lump, but it borders on poor workmanship (IMO). I think it could have been avoided by a more skilled worker.

C. This is poor workmanship. Noticeable lines and gouges like that are just sloppy work (IMO).

D. This bubble had nothing to do with hand troweling, and was caused by something else. Perhaps air bubbles in the mix, as you and others have suggested. I don't believe this to be expected, IMO, at least not as many as you have. I may have a couple of these, come to think of it, I'll try to remember to look tonight. If I do have any, it's less than a handful of 'em.

I doubt there is an official industry standard definition of what an acceptable pool finish is. If there is, I would expect it to be along these lines: "At noon on a sunny day, a pebble finish should appear to be free of any noticeable defects. At night, with the pool light on, hand-troweling waves are to be expected." It would not say that many small bubble-like bumps in the finish are acceptable.

Let's see who agrees or disagrees with my assessment...

 

[Dirk]

Here's my pool at night. My single light is just about a foot above the level of my shallow end, so it really highlights the hand-work waves. Like just about everybody that sees their new finish at night for the first time, I was taken aback. But then I learned the bit about the hand troweling. During the day, my finish looks just about flawless.

I did remember correctly, I have a couple of bumps, that may or may not be similar to yours. But I only have these two, so I never sweated them. I also have a few divots, which I expect are just more of the hand troweling flaws. They're completely invisible during the day. Because of the angle of the pool light, these few flaws and the waves are likely less than 1/4" high or low, probably even less. It's just the lighting that makes them stand out.

I did have a bothersome spot that appeared about a year after the install. My pebble is also not a brand name, just something the installer does themselves. They honored their warranty and fixed the spot without any hassle. Which is what you should expect, too.

If your builder gives you grief about making right what you don't like, then come on back and we'll fill your thread with next steps.

 

[rporonga]

Thank you for all your replies. Here are some pics taken from the edge during the day. I have the pump running all day for the startup, so that makes it hard to see any issues in the finish. The only issue that stands out is the troweling issue around the jet, where tha plastic trim sits all uneven.
The bumps may show better at night, but I cannot yet turn on the lights because the equipment is in service mode.
Next week the plaster foreman will come again and I will bring up all the comments from this thread. Also, I may be able to turn on the lights and get better pictures.

 

[rporonga]

Here is a picture of the hole they made for the pump and the exposed rebar. They later added pvc conduit grey glue and filled it up with the pebble finish.
Unfortunately I did not take any pictures of the cracks in the gunite. They developed within the first day likely due to the fast curing, on the walls and floor of the shallow end. I did not have a way to see how far down they went into the gunite, but they appeared to be caused by shrinking and not settling (if that makes any sense). I watered the gunite for the first 10 days, but the cracks were already there before I even started watering it.

 

[Dirk]

@JamesW, @ajw22, @onBalance, assuming the cracks in the shell the OP is referring to look like the ones in the pic of post #15, is that anything to worry about?

 

[ajw22]

@JamesW, @ajw22, @onBalance, assuming the cracks in the shell the OP is referring to look like the ones in the pic of post #15, is that anything to worry about?

Not if they were properly filled with hydraulic cement before plaster.